Internet is a network which connects the local area networks of thousands of firms, universities and other organizations. There is no centralized user or service directory in the net, but the user has to search the relevant subjects himself. Any kind of information can be transmitted in the network and anyone can establish an own service available for everyone. Computers having different programs and operating systems communicate using the TCP/IP (Transport Control Protocol/Internet Protocol), which is a common nomination for Internet's two most important protocols. The data to be transmitted is divided by its length into (1-1500 byte) IP-packets, which are routed to the right positions by the network router according to the address data in the packets. TCP attends to the maintaining of a reliable connection between the transmitter and the receiver. It collects the incoming IP-packets into right order and requests if necessary a retransmission. The packet addresses, i.e. the addresses of the computers in the network, consist nowadays of four FIGS. 0-255 separated by dots, which four number combination is called the IP-address (IPv4). The address is hierarchical, the first part of the address specifying the network number, generally the national prefix comes first, and the latter part tells the computer number within the network. The computer is given an IP-address when connected to Internet. The use of the addresses is facilitated by the network DNS-address service (Domain Name Service), which converts the computer names into IP-addresses and vice versa. The user can therefore refer to the names of the computers and the services instead of their numeric addresses. As the DNS-service is completely distributed to cover different parts of Internet-network, the separate local area network Domain Name Servers can inquire addresses from each other if required.
The rapid growth of Internet services and users will with in a few years cause the traffic in the net to tangle. As a result of this the TCP/IP-protocol may have to be substituted by a more developed link protocol. The change is also urged by the running short of Internet-addresses, especially c-class addresses, and by the poor applicability of the IP-traffic as now to real-time data transfer.
Almost all Internet-services are used based on the client server-principle, i.e. the client program in the user's computer gets in connection with the service provider server program, which then performs the work. E-mail is perhaps the most used service, which a private user can utilize by purchasing a personal mail-box from an Internet connection provider. The private user can then retrieve into his work station the messages from the network server (mail office) in the network, using POP (Post Office Protocol).
WWW (World Wide Web) has become the most important service form. It is a worldwide WWW-server network containing the HTML-documents (HyperText Markup Language) WWW is a hypermedia-network, which means that it only exists virtually, i.e. in electronic form. The hyperdocument is one entity, which can contain text, pictures, sound, moving picture. The document can comprise several pages. Some words or pictures in the text are links distinguishable on the screen or display, the activation of which by clicking starts the transfer to the user, to an invisible URL-address (Uniform Resource Locator) referred to in the link armature and brings a new document to the screen. Every WWW-server has a defined root, usually containing the file intended to be watched first. This is usually called the home page. Moreover every subdirectory generally contains a file which is the initial document of this directory. WWW can be accessed both with graphic user interfaces such as e.g. Mosaic, Netscape and Cello and text-based user interfaces such as e.g. Lynx.
A hyperdocument has usually a webmaster, who updates the document data.
A home user or a small company without an own local area network and not having direct access to the Internet computer can use the SLIP- (Serial Line Internet Protocol) or the PPP-(Point to Point Protocol)-connection or the terminal link program to get in contact with the Intern et computer. This computer is here called a connecting node, as from the Internet viewpoint it is one node having an address and represents to the user an access point to Internet. The node can e.g. be according to FIG. 1. The average home user has not a local area network to connect to Internet, but in accordance with FIG. 1 the user can have access through the public switching telephone network (PSTN) to the local are a network of some Internet contact company either from the ISDN user interface of the exchange or switch 4 by means of the computer 2 provided with an ISDN-adapter or from an analog user interface of the exchange or switch connected through a modem 3 to the computer 1 serial line port (RS232-, i.e. the so called COM-port(serial interface)). The computer 1 can instead of an external modem be provided with an internal modem card.
Those using the dial-up network analog user interface and modem 3, are connected to the modem pool 5 linked to the router 6. The connection is established so that the computer 1 data communications program sets up a connection to the router 9, which serves as DHCP-server. The local area network and thus also the users 1 and 2 are connected to the Internet-world through the router 10. Router 10 routes the transmitted IP-packets according to their addresses to the right networks and functions also as a traffic delimiter if necessary.
The connection described above between the user and the contact company local area network is usually for the home users of an ordinary switched telephone network, but the contact companies also offer fixed connections in co-operation with the teleoperator.
Computer 7 handling the users' E-mail traffic is an important component in the local area network, being the one from which the computers 1 and 2 can fetch their E-mail using the POP protocol. Another important local area network component is the local PROXY-server 8. The PROXY-server can also be behind the router 10 in Internet. The PROXY-server acts as the network service cache and also as a gateway between the company's own local area network and Internet. It saves into its own memory e.g. the latest retrieved Internet files or WWW-pages, from which the users in the same PROXY-server can quickly reread them into their own computer.
To enable the user 1 who has connected his computer via a modem to a public telephone line, to use graphic client programs and the WWW-browsing, SLIP (Serial Line Internet Protocol) or PPP (Point to Point Protocol) is used in the data transfer between the user and the local area network. The protocol converts the modem line into an Internet cable and extends the Internet TCP/IP-telecommunication link to include the public telephone line from one modem to another, in the figure between terminal 1 and router 6. SLIP enables the Internet-communications using the computer serial line port, whereby the computer behind the serial interface becomes to a work station connected to the network.
One special feature of Internet is that the use of it has up till now been almost free of charge. Internet communication costs have been covered by public means, by authorities or universities. The user has during one session been able to be in connection with computers all over the world and receive a great amount of information free of charge. The contact company offering Internet-connections charges of course a connection (access) fee and a fixed monthly fee.
The extent of the network and the amount of users have caused companies, communities and also private persons to produce an own Internet WWW-page to present their products and services. The aim of the companies and the communities is to obtain public attention and to create new contacts with prospective customers.
A WWW-based ordering system has been suggested enabling the merchant to order the desired products from different distributors using his own computer. In this system the invoicing is however made traditionally afterwards outside Internet. Some progressive businessmen already offer this kind of service merely on an experimental basis.
For the electronic trading it has been suggested a system in which the seller gives a general presentation of his shop and its products on his own home page. From this page there are links to the complete product catalogues. Having chosen the product, the buyer clicks a certain link, which brings an order form on the screen. The buyer fills in the form and adds his credit card number. After receipt of the order, the seller's server generates a confirmation message and sends it to the buyer. The disadvantage of such an electronic trade is the security risk involved in the transfer and handling of the credit card number.
The common feature of all the suggested ordering methods is that the invoicing is done traditionally, always separately and afterwards. This involves however the risk that the client orders the product without any intention to pay for it. It is also possible for someone to order in the false name and have the product delivered to a third party, or someone who snatched the credit card number makes orders and the invoice is sent to the right owner of the credit card.
One solution to the problems mentioned above would be to connect the service charging to the telephone bill for such users, who according to FIG. 1 use the dial-up telephone network for the connection to Internet. This would improve the reliability of ordering, as the origin of the call is known and excludes the possibility of ordering services anonymously. The present arrangements do not however enable this, as the operator charging for the calls does not know the IP-address of the user's computer. Furthermore, the user's telephone number, the IP-address of the computer and the chargeable Internet-service prices are separate information.